Pith Number

pith:5I7RLFWY

pith:2021:5I7RLFWYNJGFS2RIF35THXBMOF

not attested not anchored not stored refs pending

On time-parallel preconditioning for the state formulation of incremental weak constraint 4D-Var

Amos S. Lawless, Ieva Dau\v{z}ickait\.e, Jennifer A. Scott, Peter Jan van Leeuwen

arxiv:2105.09802 v2 · 2021-05-20 · math.NA · cs.NA

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{5I7RLFWYNJGFS2RIF35THXBMOF}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-07-05T03:06:46.937403Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

ea3f1596d86a4c596a282efb33dc2c71477614e9de348542081e6e6465e0d2a6

Aliases

arxiv: 2105.09802 · arxiv_version: 2105.09802v2 · doi: 10.48550/arxiv.2105.09802 · pith_short_12: 5I7RLFWYNJGF · pith_short_16: 5I7RLFWYNJGFS2RI · pith_short_8: 5I7RLFWY

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/5I7RLFWYNJGFS2RIF35THXBMOF \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: ea3f1596d86a4c596a282efb33dc2c71477614e9de348542081e6e6465e0d2a6

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "063a2e1a6615290aca8c8a82257149292ee66371e5bd345e11b314c3b899f6e7",
    "cross_cats_sorted": [
      "cs.NA"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "math.NA",
    "submitted_at": "2021-05-20T14:57:13Z",
    "title_canon_sha256": "f5c0fd5d4b81bae064b1a5cf45f0f461ed7fa1e323671bf9d8ce74d033dd7c99"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2105.09802",
    "kind": "arxiv",
    "version": 2
  }
}